Pinch valve



y 6, 1952 w. F. BUTLER 2,595,511

PINCH VALVE Filed Oct. 29, 1948 j Z 1 INVENTOR.

fl m/m/ 1. 50/752 Patented May 6, 1952 PIN CH VALVE William F. Butler,Oakland, Calif., assignor to Cutter Laboratories, Berkeley, Calif., acorporation of California Application October 29, 1948, Serial No.57,209

1 Claim.

controlling the flow of fluid through a section of collapsible tubingand particularly useful for controlling the flow of blood from a blooddonor to a flask.

When taking blood from a donor, a hypodermic needle connected through asection of the collapsible tubing with a flask is inserted in the veinof the donor and then communication with the flask is established byopening a pinch valve associated with the tubing. Thereafter a rotarymovement is imparted to the flask to agitate the blood going thereintowith a small volume of sodium citrate contained in the flask and whichserves to prevent the blood from coagulating. During this operation dueprecautions must be taken to avoid pulling the hypodermic needle awayfrom the donor for in the first place any movement of the needle ispainful to the donor, and if, by chance, the needle is pulled away fromthe donors vein it must of necessity be reinserted and this operation isat best disagreeable. Furthermore, precautions must be taken to preventthe introduction of any air into the blood for the introduction of airinto the veins-of a patient cannot be tolerated.

More specifically, the object of this invention is the provision of apinch valve constituting an improvement to the valve shown in the Butleret a1. Patent No. 2,309,302, which can be placed in its operativeposition over the collapsible tubing without the necessity of threadingthe tubing to the pinch valve and which enables the operator preciselyto control the flow of blood through the tubing and into its associatedflask.

These and other objects of the invention will be apparent from theensuing description and the appended claims.

The invention possesses other advantageous features, some of which, withthe foregoing, will be set forth at length in the following descriptionwhere that form of the invention which has been selected forillustration in the drawings accompanying and forming a part of thepresent specification is outlined in full. In said drawings, one form ofthe invention is shown, but it is to be understood that it is notlimited to such form, since the invention as set forth in the claims maybe embodied in a plurality of forms.

Referring to the drawings:

Fig. 1 is a top plan view of a pinch valve embodying the objects of myinvention.

Fig. 2 is a side elevation of the pinch valve shown in Fig. l.

Fig. 3 is a vertical mid-section taken on the line 3-4 of Fig.1.

Fig. 4 is a right end elevation of the valve shown in Figs. 1 and 2.

Fig. 5 is a fragmental side elevation of the right end of the valveshown in Figs. 1 and 2 showing the roller of the pinch valve as itapproaches its open position.

Fig. 6 is a right end elevation of my valve similar to Fig. 4 but withthe roller of the valve in its fully opened position.

As shown in these various figures, my valve includes a channel generallydesignated by the numeral I and including a base 2 and upstand ing sides3 and 4, arranged to receive a section 5 of rubber tubing having adiameter somewhat smaller than the width of the channel I. The sides 3and 4 are wedge shaped with respect to the longitudinal axis of thechannel and are overturned at their upper edges so as to form outwardlyextending side wings 6 and l. Formed in the sides 3 and i are inclinedcam slots or trunnion ways 8 and 9, the upper edges of which areserrated as at It Forming an extension of the upper right hand end ofeach of the trunnion ways 8 and 9 are U-shaped slots I I and I2terminating in re-entrant openings [3 and I4 formed in the wings 6 andl.

Accommodated within the channel I is a knurled roller I5 mounted onopposed axially aligned trunnions I6 and I! receivable in the opposedtrunnion Ways 8 and 9. The trunnion Il terminates in a sphere I8 of adiameter larger than the width of the trunnion ways 8 and 9. In theassembly of the roller I5 and the channel I the sphere I8 is insertedthrough the re-entrant opening M which from an inspection of Fig. 1 willbe seen to be of spherical form. Initially the reentrant opening I4 isof a diameter larger than the sphere I8. After the sphere I8 has beenintroduced through the re-entrant opening I4, the diameter of thisopening is reduced in size by a conventional swaging operation, toprevent the trunnion I I from passing through the re-entrant opening I4or through its associated trunnion way 9. The opposed tninnion I 6 maythen be passed through its re-entrant opening I3 and both trunnionsmoved downwardly, then upwardly, within their associated U-shaped slotsI2 and I3 and into their respective trunnion ways 8 and 9. As thetrunnions enter the trunnion Ways 8 and 9 the lower surface of theroller I5 comes into engagement with the upper edge of the section ofthe tubing 5 and if then the roller be moved to the left as viewed inFigs. 1, 2, 3 and 5, the tubing will be progressively pinched from itsfully open position as shown in Fig. 2 to its fully closed position asshown in Fig. 3. The knurled upper edge of the trunnion ways 8 and 9serves to retain the roller 15 in any predetermined position along itstrunnion ways.

From'this description it will be seen that I have provided a pinch valvewhich can be placed on or removed from a section of tubing without thenecessity of threading the end of the tubing through the valve and bywhich a very precise control of the flow of the fluid through the tubingcan be readily maintained at all times.

I claim:

A device of the character described for controlling the fiow of fluidthrough a section of flexible tubing comprising: a channel including abase and a pair of upstanding sides for the accommodation of saidsection of flexible tubing, said sides having outwardly extending wings;trunnion guide ways formed in said sides, said guide ways being inclinedlongitudinally with respect to said base and having re-entrant openingsat the high ends thereof extending through 'said wings, and said guideways being serrated only on their upper edges; and a roller receivablein said channel and mounted on trunnions receivable in said guide ways,the end of only one of said trunnions being enlarged to prevent itspassage through its associated guide way.

WILLIAM F. BUTLER.

REFERENCES CITED The following references are of record in the file. ofthis, atent:

UNITED STATES PATENT

